dx Round Robin

[ShayF2]

Hello. I'm a scripter for MTA:SA, many of you have seen me on the forums, posting helpful things on your threads. Today I need some help. This code below is code to create dx gridlists. I use arrow keys to control what I select. However when the gridlist can show 5 items at a time and I only put 3 in, it seems to overlap, thinking that there is an extra index. So long as the gridlist has at least 5 items it'll work perfectly fine. Could someone please help me fix this round robin effect?
 

function dxCreateGridlist(x,y,w,h)
    local self = dx('gridlist','default',x,y,w,h)
    if self then
        self.itemHeight = 25
        self.maxItems = math.floor(self.h/self.itemHeight)
        self.bgColor = tocolor(0,0,0,180)
        self.selectedColor = tocolor(80,80,80,180)
        self.textColor = tocolor(255,255,255,200)
        self.startPos = 1
        self.endPos = 20
        self.currentItem = 1
        self.itemSpacing = 2
        self.selected = 1
        self.items = {}
       
        self.draw = function()
            self.endPos = self.startPos+self.maxItems
            local yOff = 0
            for i=self.startPos,self.endPos do
                if self.items[i] then
                    if i == self.selected then
                        dxRect(self.x,self.y+yOff,self.w,self.itemHeight-self.itemSpacing,self.selectedColor)
                        dxText(self.items[i].text,self.x,self.y+yOff,self.w,self.itemHeight-self.itemSpacing,self.textColor)
                    else
                        dxRect(self.x,self.y+yOff,self.w,self.itemHeight-self.itemSpacing,self.bgColor)
                        dxText(self.items[i].text,self.x,self.y+yOff,self.w,self.itemHeight-self.itemSpacing,self.textColor)
                    end
                    yOff = yOff+((self.itemHeight))+self.itemSpacing
                end
            end
        end
       
        self.addItem = function(text)
            local item = {}
            item.text = text
            table.insert(self.items,item)
        end
       
        self.itemsClear = function()
            for k=1,#self.items do
                table.remove(self.items,k)
            end
        end
       
        self.onKey = function(key,state)
            if state then
                if key == 'num_8' then
                    if self.selected < self.startPos then
                        if self.selected <= 1 then
                            self.startPos = #self.items-self.maxItems
                            self.selected = #self.items
                        else
                            self.startPos = self.startPos-1
                        end
                    else
                        self.selected = self.selected-1
                    end
                elseif key == 'num_2' then
                    if self.selected > self.endPos then
                        if self.selected >= #self.items then
                            self.selected = 1
                            self.startPos = 1
                        else
                            self.startPos = self.startPos+1
                        end
                    else
                        self.selected = self.selected+1
                    end
                elseif key == 'num_enter' then
                    outputChatBox(self.items[self.selected].text)
                end
            end
        end
       
        table.insert(draw,self)
        return self
    end
end

 

[IIYAMA]

Please give me some context about how it overlaps, it makes it easier for me to find the problem.

 

self.endPos = self.startPos+self.maxItems

Also this should be limited to the total items in the gridlist for performance reasons. (Unless you do add a grid)

 

Debug the yOff variable for every item, just to be sure that the problem is here.(and show result)

 

 

 

Edited January 18, 2018 by IIYAMA

[ShayF2]

I think I figured out the issue.

Say I have 3 items in the gridlist and the maxItems is calculated to be 5. The start position would change to -2 when it's range is only 1 to 3. This is because it does the math self.startPos = #self.items-self.maxItems.

I'm not totally sure that fixing this will fix the problem, I will test it when I have the time. Today I don't really have the time.